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I'm personally gonna try a blond Driggs River next (think it will be inferior but ya never know)...... Comments thoughts or recommendations?  (Rob Smith)

You bring up an interesting point. Well more than one, but one I'll comment on. And this isn't intended to hijack the thread, just send it off on a tangent. Thus the subject change.

Most conventional thinking holds that flamed bamboo is stiffer than blonde bamboo and produces rods with a quicker feel. We haven't had this discussion in awhile, so what do others of you think? Are flamed rods quicker? Are blonde rods quicker? No difference? I'll tell you what I think later. (Harry Boyd)

I think overall (as my wife always seems to answer when given a choice) it depends but I do feel that if one were able to test two strips that were EXACTLY the same in terms of weight and or power fiber density, taper cut, etc, I would venture forth in saying the flamed strip would be a bit stiffer than the blonde - This is not to say however that the difference could not be made up with a slight taper change. As well I think the blonde strip would have greater flexing ability IE: bend more before fracturing. Not sure if Bob Milward would agree but that’s how I've found it. (Rob Smith)

That has always been the classical, if empirical, view.

It is also what seems to me to actually happen, but I have not run any stress/srain experiments to prove it.

I did once really overcook some cane to make a matching top, and it subsequently broke, exactly as the original had done and in the same place, with a very short sharp fracture zone. Certainly not the same as a piece of raw cane from the same(crappy) culm. (Robin Haywood)

When you denote cane as blond, are you meaning not flamed, or not heat-treated. I don't flame the strips but heat treat at 390 degrees. While most of the rods are quite light in color, I'm not sure if they would meet your definition of blond (certainly not a bleached blond). (Bill Lamberson)

Dug the Milward book back out. Section 1.2 covers this topic. Here's the specific quote from page 18:

"Any darkening of the bamboo color represents loss of both tensile and flexural strength, due to degradation of cellulose fiber."

I'm sure that's debated inside and out in the archives. The reasoning seems logical from a layman’s point of view. Milward concludes that the vast majority of the gain in bending strength is caused by drying...not changing the color of the power fibers with heat.

Any noticeable difference in blond and flamed bending strength is more than likely the result of a variance in moisture content. Moisture content will vary with the drying process. I don't think it has to be flamed to maximize the effect of drying. (David Bolin)

I'll toss in another couple factors:

1. What about the flaming method? The standard procedure is to flame the outside but Sir D flames the inside and that is his onlly heat treatment as I understand. How does that change the action?

2. Also if flamed what does additional heat treating do? (Larry Puckett)

To 1. Good point! Personally haven't tried the inside flaming technique but would probably place it along the lines of browntoning or oven tempering and really thus as a third style or method - not flamed or blonde. Again haven't tried yet - How do others who HAVE done it place or grade the techniques result?

To 2. Debate there but from my experiences depends on the quality of the bamboo or flame job as if done well have not noticed any change in strips if re-tempered - from my experiences lesser quality strips can be manipulated some (straightened, twisted) but I find they ultimately go back. If only lightly flamed I think additional heat will further change the bamboo properties some and that well flamed bamboo cannot be re-tempered or further manipulated without essentially compromising its overall strength. My experiences anyway. (Rob Smith)

In response to 1, I have on a couple of my own rods, it seems to do just fine except for the black residue. I just get too dirty planing the strips. If you have seen any photos of my "Twisted Miss" the light strips are flamed from the pith side and glued in with the pith side out. Those strips are almost blond. The dark strips are regular flamed strips glued in with the enamel side out. The rod has alternating light and dark strips. (Tony Spezio)

I have changed the inside flaming method a little bit. When I wire brush off the burned pith, I run water from the garden hose down the inside of the culm. Gets rid of a lot more of the soot. Since I soak the strips later wetting it doesn't matter a bit. (Darryl Hayashida)

So the culm is split in half first and then one half flamed on the inside and the other half flamed conventionally on the outside, am I following correctly?

If so, are there ANY differences in the flexibility or weight between two finished splines of differing flaming techniques (inside and outside)?? (Rob Smith)

As you might have suspected, when I first tried the inside flaming method, I compared the stiffness to a normally flamed strip (the inside flaming method leaves the appearance of the outside of the culm totally unchanged or blonde). After looking at both strips I decided I couldn't really evaluate which one was stiffer. The inside flamed strip had all it's pith burned away. The outside flamed strip still had it's layer of pith. So I planed away the pith on the regularly flamed strip. Even then it was had to tell how much pith to plane away, so the comparison was inconclusive.

So, the only thing I would offer as an advantage to inside flaming is it is a way to make blonde rods without having to make or buy an oven.

Getting back to the original question, I would suspect that it would depend on the oven temperature and time in the oven for the blonde strip and the amount of flaming that the flamed strip got. In other words how much moisture is left in each strip. (Darryl Hayashida)

My own personal feeling and observations on this is that heating has a cumulative affect. As was said earlier, in the heating process you are creating a bunch of double bonds. The more heat you apply the more double bonds are created, and the more you have the more brittle the cane will be. Just the right amount of heat gives the perfect combination a strength and resilience. A little touch too much and brittleness increases the chance of internal stress fractures in the cane, which over time accumulate to the point that external fractures occur. The BIG question that keeps resurfacing is how much heat is just enough and how much is too much?  (Larry Puckett)